analysis of tall buildings with bundled tube system subjected to wind and earthquake loads

at present, the tubular structural systems are mainly used in tall buildings to withstand earthquake loads. although it is possible to analyse the structure by finite element methods using standard three dimensional programs, the system is generally time-consuming and expensive in the primary design work. in this paper, for the analysis of framed-tube systems, a simple method was studied and developed for bundled-tube systems and corresponding formulas for horizontal and vertical deflections were obtained. by replacing the discrete structure with and equivalent tube or replacing the multicell tube with orthotropic plates and making simple assumptions regarding the stress distributions in the structure, simple closed-form solutions using the were obtained. standard load cases including uniformly distributed load, triangularly distributed load, and point load at the top were applied. by this method, a new computer program was developed, called tsap (tubular structural analysis program). the <> results were compared with more accurate results obtained by famous finite element computer programs. the runtime for this program was about 2% of the runtime for other existing programs.